This is so blindingly obvious that I cannot understand how can it be denied… Let’s make a minor change to illustrate their irrationality:
“This dish is too salty” has no truth value, but “this dish is too salty for PA” does… or
“This weight is heavy” has no truth value, but “this weight is heavy for this child” does… or
“The bridge is too far” has no truth value, but “the bridge is too far for a quadriplegic” does… or
“The music is too loud” has no truth value, but “the music is too loud for an autistic person” does…
or zillions of other examples. The amount of salt in the dish, or the weight of the rock, or the distance of the bridge, or the decibel of the music are all objective values, but the relationship with the observer is NOT.
This has been pointed out many times, but the other party keeps digging their collective feet into the sand, or putting their collective heads into the sand, and keep singing: “I can’t hear you! I can’t hear you!”. Pitiful, really.